Figure 3

Power deposition Q in the central plane aligned with the graft length from the FDTD model. Q in the central plane aligned with the graft length was calculated for the (a) 1.5-MHz transducer (0.6 W incident power) and (b) 3.2-MHz transducer (0.375 W incident power), focused on the back wall. Intimal hyperplasia models are shown. With the 1.5-MHz transducer, the ePTFE absorbed more power at the front wall, leaving less to be absorbed in the rear graft wall, while the 3.2-MHz transducer deposited most of its power in the rear wall of the graft.